diff --git a/content/en/functions/openapi3/Unmarshal.md b/content/en/functions/openapi3/Unmarshal.md
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+---
+title: openapi3.Unmarshal
+description: Unmarshals the given resource into an OpenAPI 3 document.
+categories: []
+keywords: []
+action:
+  aliases: []
+  related: []
+  returnType: openapi3.OpenAPIDocument
+  signatures: ['openapi3.Unmarshal RESOURCE']
+---
+
+Use the `openapi3.Unmarshal` function with [global], [page], or [remote] resources.
+
+[global]: /getting-started/glossary/#global-resource
+[page]: /getting-started/glossary/#page-resource
+[remote]: /getting-started/glossary/#remote-resource
+[OpenAPI]: https://www.openapis.org/
+
+For example, to work with a remote [OpenAPI] defintion:
+
+```go-html-template
+{{ $url := "https://raw.githubusercontent.com/OAI/OpenAPI-Specification/main/examples/v3.0/petstore.json" }}
+{{ $api := "" }}
+{{ with resources.GetRemote $url }}
+  {{ with .Err }}
+    {{ errorf "%s" . }}
+  {{ else }}
+    {{ $api = . | openapi3.Unmarshal }}
+  {{ end }}
+{{ else }}
+  {{ errorf "Unable to get remote resource %q" $url }}
+{{ end }}
+```
+
+To inspect the data structure:
+
+```go-html-template
+<pre>{{ debug.Dump $api }}</pre>
+```
+
+To list the GET and POST operations for each of the API paths:
+
+```go-html-template
+{{ range $path, $details := $api.Paths }}
+  <p>{{ $path }}</p>
+  <dl>
+    {{ with $details.Get }}
+      <dt>GET</dt>
+      <dd>{{ .Summary }}</dd>
+    {{ end }}
+    {{ with $details.Post }}
+      <dt>POST</dt>
+      <dd>{{ .Summary }}</dd>
+    {{ end }}
+  </dl>
+{{ end }}
+```
+
+Hugo renders this to:
+
+
+```html
+<p>/pets</p>
+<dl>
+  <dt>GET</dt>
+  <dd>List all pets</dd>
+  <dt>POST</dt>
+  <dd>Create a pet</dd>
+</dl>
+<p>/pets/{petId}</p>
+<dl>
+  <dt>GET</dt>
+  <dd>Info for a specific pet</dd>
+</dl>
+```
diff --git a/content/en/functions/openapi3/_index.md b/content/en/functions/openapi3/_index.md
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+---
+title: OpenAPI functions
+linkTitle: openapi3
+description: Template functions to work with OpenAPI 3 definitions.
+categories: []
+keywords: []
+menu:
+  docs:
+    parent: functions
+---
+
+Use these functions to work with OpenAPI 3 definitions.